Compressor



March 10, 1925- 1,529,258

C. E. L. LIPMAN COMPRESSOR Filed "Sept. 2a, 1921 Patented Mar. 10, 1925.

UNITED STATES PATENT OFFICE.

CARL E. L. LIPMAN, OF BELOIT, WISCONSIN, ASSIGNOR TO LIPMAN REFRIGERATOR CAR & MANUFACTURING COMPANY, OF BELOIT, WISCONSIN, A CORPORATION OF DELAWARE.

COMPRESSOR.

Application filed September 26, 1921.

In a compressor of this type which is subjected to practically continuous usage for long periods of time, it is essential that provision for adequate lubrication of the working parts be made and also that leakage of the ammonia be effectually prevented. Furthermore, I have found that it is very detrimental to the successful operation of an ammonia system if oil be permitted to enter the system and become mingled with the ammonia.

One of the primary objects of my present invention is to provide a compressor which will cfliciently compress ammonia gas and which will preclude the leakage or escape of the gas and will also provide for adequate lubrication of the compressor and at the same time prevent the lubricating oil from entering the ammonia system.

For the purpose of facilitating an understanding of my invention, I have shown on the accompanying drawing one preferred embodiment thereof, from an inspection of which, when considered in connection with the following description, my invention and many of its inherent advantages should be readily understood and appreciated.

Figure 1, is a vertical sectional view through a compressor embodying my invention; and

Fig. 2, is a plan view of the piston crosshead 44, removed from the compressor.

It will be observed that the compressor comprises an upright hollow casting 1, formed at its bottom to provide a suitable base or pedestal 2 the casting being open from side to side to permit the introduction thereinto of the crank shaft 3 equipped with the crank 4. v

The outer end of the crank shaft is supported in a bearing 5 formed in the cap 6 Serial No. 503,255.

which provides a closure for one side of the main casting to which it is securely attached by lag bolts 7. The shaft at the opposite side of the crank is supported in a bearing 8 carried by the closing plate 9 which forms a closure for the main casting at that side of the machine, this plate be ing secured to the main casting by lag bolts 11. The shaft projects outwardly thru this member 9 as shown, and a stufiing box 12 is utilized to seal the opening around the. shaft and prevent escape of the oil from the crank case along the shaft. Power is applied to shaft 3 to rotate the crank, at apoint outside the crank case where the shaft may be equipped with a belt pulley or may be directly connected to a motor if preferred. Itwill thus be manifest that I have provided a crank case which is entirely closed and which may be filled with oil to provide adequate lubrication for the moving .parts.

The upright casting 1 carries a' tubular crosshead guide indicated by reference character 13 which snugly fits within the upright casting 1 into which it is inserted from the upper end thereof. A plurality of screw bolts 14 threaded thru the side of the up right member 1 and engaged at their inner ends in a circumferential groove 15 formed in the member 13 serve to securely lock the member 13 in position.

The piston cylinder consists of a member 16 shaped at its lower end to snugly. fit within the upright member 1 and adapted to rest upon the upper end of the upright memher to which it is securely attached by bolts 17 leakage between the members being precluded by a packing ring 18. The member 16 is centrally bored to provide the cylinder in which the piston reciprocates and is cored to form a surrounding chamber 19 adapted to contain a circulating cooling medium, thereby serving the same function as a water jacket of a gas engine. The top of the cylinder proper is closed by a cap 21 which is shaped on its inner face to provide a guide 22 for the stem 23 of the exhaust valve 24 which is urged against its seat 25 formed in the member 16 by a coiled expansion spring 26. The upper end of the water chamber is closed by a cap plate 27 secured by bolts 28 to the outer wall of the member 16. Exhaust port 29 extends radially from the cylinder above the valve 2 1 and a pipe 31 connected with this port serves to conduct the compressed ammonia to the con-.

main member -1-surroundsthe cylinder be-' neath the piston andcommunication is es tablished between this passage and the,in-

terior of the cylinder thru a series of radial ports 41 Theinlet pipe. 42 leading from the absorber of the system is connected with the'chamber 39 so that the incominggas passes from the'pipe 42 into the chamber 39 and thence thru the ports 41 into thercylinder' beneath the piston The piston .is actuated by a rod 43 'con-.

nected at its upper end-to the piston andat its lower end to an open guide or crosshead 44 adapted to reciprocate in the crosshead guide 13,this guide in turn being reciprocated from the crank 4 by a connecting rod 45. It will be observed that the guide 44 serves to maintain the lower end of the rod 43 in absolute alinement withthe axis of the cylinder so that radial or angularimovements of the piston which might result in undue wear or leakage, are obviated. It will he further observed that the crosshead is open from end .to end as indicated by reference numeral 44 at each sided-f the connect-1 ing rod pin and the diametrical spiderinto which the lower end of the rod43 is threadprevents the ammonia gas frompassing downwardly into the crank case altho escape of the gas downwardly into the crank case'r-is not materially detrimental since-the crank case is entirely closed and effectually sealed against the escape of either oil or gas out into the atmosphere.

The seal between the piston and the cross head 44 consists of a stufling box. formed by a lower member 46, an upper member 47 and interposed packing material 48 surrounding the guide rod 43. The lower mem ber-46 of the stuffing box is attached :by screws 49 to the upper end of the member 13 before theupper cylinder member 16 is aston around the valve 34.

sembled with the upright member 1. The upper member 47 is continuously urged toward the member 46 to maintain the packing material 48 under compression by means of coiled expansion springs 51 interposed be tween the member 47 and the heads of elongated screws 52 passing loosely thru aper- .tulr.es -in the margin of member '47 and threaded into tapped openings in member 46. It .Wlll .thusxbe manifest that by this construction I have provided an efl'ectual crankcase of the compressor.

In the operationof the machine, ammonia gas is drawn into the cylinder beneath the piston upon the up stroke of the piston, and uponthe down stroke it passes thru the pis- A check valve (not shown) in the pipe 42 serves to prevent thegas'from backing .up into the absorber Upon the up stroke of the piston the gas is compressed and finally expelled past the valve 24 and out thru the pipe 31 to the condenser.

- From the foregoing it will be observed that Ihave provided a compressor in which ammonia gas is effectually prevented from escaping, and loss of lubricant from the crank case through the compressor cylinder by a combination of elements provided by the construction disclosed herein, to certain phases of which attention will now be more particularly directed. It will be noted that both'the crank case chamber and the chamber in which the crosshead 44 reciprocates are closed to the atmosphere and sealed from 'thepiston cylinder by the stationary pack- "ing device comprising in this instance'the member-s46 and 47 and the interposed packseal between the ammonia system..and the ing as described above. By closing both said chambers to the atmosphere I am en-J abled to employ a comparatively small pack-..

ing. on the rod 43 because. this packing or :sealingdevicefunctions primarily for keep- .ing oil from.entering the piston cylinder rather than being of such large proportions and requiring such heavy pressure and tight seal; as :to prevent'the escape of ammonia fumes to thechambersbelow. Consequently friction andwear on this packing is reduced andwit is comparatively long-lived for thepurpose intended. The incidental escape of ammonia fumes to theqchambers below is not detrimental because such chambers are structurally closed to the atmosphere. In fact theionly possible escape is. through the stuffing box 12 and'this is efiectually precluded not only by the function of the pack- .ingbut by an oil seal provided by maintain-.

moniagasthrough the stufling box, espe- 35 ing an oil level in the crank case above the cially inasmuch as the pressure in the crank case is comparatively low. This oil level will be maintained over a long period without replenishing because the oil consumption is very low due to the means provided herein against loss.

It will be further observed that this method makes for greater practicability in compressors of this type because these compressors are used to a great extent in domestic refrigeration systems. Escape of ammonia fumes from such compressors is ob viously very objectionable. The present invention provides in a comparatively simple and practical way for preventing such leakage; and it will be observed that in addition to closing the crosshead chamber and the crank shaft chamber to the atmosphere and providing packed joints at the only two outlets, I have further reduced the chance for escape by utilizing an oil seal for the crank shaft packing, as shown in Fig. 1. The packing against a rotating part such as the crank shaft will maintain a much tighter seal than the smaller packing against a reciprocating part such as rod 43, consequently even though the oil level should drop in the c'ank case the liability of fumes escaping is reduced to a minimum. Adequate lubrication of the crosshead guide walls is also effected in asimple and practical manner, especially by reason of the enclosed crosshead chamber and the provision for splash lubrication through the crosshead. And inasmuch as all working parts are closed from the outer atmosphere all dust, dirt and other foreign matter is excluded, thus further aiding in the general efficiency of compressors of this type.

From the foregoing it will be manifest that my invention in its broader aspect contemplates a suitable casing providing a cylinder for the ammonia pumping piston and a crosshead cylinder or guide in axial alignment and a crank case communicating with said guide, all of which are structurally closed to the atmosphere, and in which a stationary sealing device separates the piston cylinder and the chamber in which the crosshead reciprocates and surrounds and embraces the rod connecting the crosshead and piston so as to provide circumferential contact with the said rod.

It is believed that my invention, its mode of operation, and many of its attendant advantages will be understood and appreciated from the foregoing without further description, and it should be manifest that the details of construction shown and described are capable of considerable modification without departure from the essence of the invention as defined in the appended claims.

I claim:

1. In a compressor, the combination of a hollow member forming at one end a portion of a closed crank case, a cylinder carried by said member and provided with inlet and outlet ports, a crosshead guide carried by said member between said cylinder and the crank case, a crosshead reciprocable in said guide, a piston reciprocable in said cylinder, a rod connecting said crosshead with said piston, and a stationary sealing device surrounding and embracing said rod for preventing leakage between the cyl inder and the crank case, said crosshead being open to permit the passage of oil therethrough to lubricate said rod and the walls of said guide.

2. In a compressor, the combination of a cylindrical member having a transverse opening through its lower end forming part of a closed crank case, means closing the ends of said opening to seal said crank case, a crank in said case, a cylindrical guide mounted in said member just above said crank case, an open crosshead reciprocable in said guide by said crank, a cylinder rigidly mounted upon and extending into the upper end of said member, the space between said cylinder and said guide being enclosed by the walls of said member, a piston reciprocable in said cylinder, a rod connecting said piston with said crosshead, and a stuffing box disposed within said member and through which said rod ext-ends, whereby the cylinder is sealed from the crank case, lubrication of said rod from the crank case being permitted through said open crosshead.

S. A compressor comprising, in combination, a casing structure providing a piston cylinder, a cylindrical guide and a crank case, the cylinder and guide being coaxial and the guide being interposed between the cylinder and crank case, the cylinder having an inlet and an outlet portion, a piston reciprocable in the cylinder, a crosshead reciprocable in the cylindrical guide, a rod connecting the crosshead and piston, a crank shaft journaled in the crank case and connected by a connecting rod to the crosshead, a stationary sealing device interposed between and separating the cylinder and chamber in which the crosshead reciprocates, said device surrounding and embracing the piston rod and having a circumferential sealing contact thereabout, one end of the crank shaft extending beyond the crank case for connection to a driving means, a stufiing box for said end of the crank shaft, the crank shaft chamber and the crosshead chamber being structurally closed to the atmosphere, whereby to effectually prevent escape to the atmosphere of gases being pumped by the compressor and to prevent loss of oil from the crank case through the compressor cylinder.

4-. A compressor comprising, in combination, a casing structure providing a piston cylinder, a cylindrical guide and a crank case, the .cylinder and guide being coaxial and the guide being interposed between the cylinder and crank case, the cylinder having an inletand an outlet portion, a pistonreciprocablein the Cylinder, a crosshead reciprocable in the cylindrical guide, a rod connecting the cross head and piston, a crank shaft journaled in the crank case and connected by a vconnecting rod to the crosshead,,a stationary sealing device interposed between and separating u the, cylinder [and chamber in which the crosshead .reciprocates, said device surrounding andembracing the piston rod and having a sealinglcontact thereabout, one end of thecrank shaft extending beyond the vcrank case; for connection to a driving means,.a stuffing box for said end of the crank shaft, the crank shaft chamber and thecrosshead chamber being structurally closed to the atmosphere, whereby to effectually preventescape to the atmosphere ofgases being pumped b i the. compressor and to prevent loss of Q1] from the crank case through the compressor cylinder, the crosshead being open from. end to .end to permit oil from the crank case toisplash upu into the crosshead chamber for lubricating the guide'wall thereof.

An ammonia compressor comprising,

a in combination, a casing structure providing a piston cylinder, a crank case and an interposed crosshead guide chamber, an ammonia pumpingpiston reciprocable in-the cylinder, a crosshead reciprocable in, the guide chamber and guided by the walls thereof, a rod connecting the crosshead and piston, a crank shaft journaled in the crank case and connected by a connecting rod to the crosshead, a stationary sealing device teem separating the piston cylinder and the crosshead ,gu ide] chamber and including a packing surroundin and embracing the piston rod and provi ing' circumferential sealing contact therewith, and the crankcase and crosshead guide chamber being; structurally I closed to: the atmosphere, whereby toprevent escape ofamnionialfumes into the .atmosphere and to prevent loss of; oil from the crankcase through the ammonia cyr n v a,

6. A vertical ammonia compressor comprising, in combination, a casing, structure provid ng a p ston cyl nder and, a cylindrical crosshead guide n vertical alignment, and

a crank case communicating with the lower therewith, a crank, shaft journaled in the crankcase and connec tedby; a connecting rod to thecros shead, one end only of the crank shaft extending bey on d the crank case,

a stuffing box between said. extended end: of the crank shaft andthe crankcaseathe crank case chamber and the cross hea d guide, chamber being structurally closed to the atmosphere, and an oil sealgfor the stuffing, box, whereby to prevent leakage of ammonia fumes to the, atmosphere and to prevent loss of oil through the piston cylinder.

CARL E. LQLIPUMAN. 

